A printed circuit board (PCB) is formed by printing a circuit line pattern on an electric insulating substrate with a conductive material such as Cu, and is called a board just before electronic components are mounted. That is, the printed circuit board means a circuit board which is configured such that to closely mount many kinds of electronic devices on a flat board, positions for mounting each component are determined, and a circuit pattern for connecting the components is printed on and is fixed to a surface of the flat board.
Meanwhile, to cope with the recent trend of high performance and small-sized electronic components, a buried pattern capable of making a surface of the board even at the same time as reducing a thickness of the printed circuit board has been used.
FIG. 1 illustrates a general buried-type printed circuit board.
As shown in FIG. 1, a buried-type printed circuit board 10 is configured such that a buried pattern groove 2 is formed on a surface of an insulating substrate 1, and a circuit pattern 3 is formed by burying the buried pattern groove 2 using plating.
In the printed circuit board 10 on which the buried pattern 3 is formed, due to a formation structure of the base circuit pattern and a contact part, a bonding force with an insulating member becomes very high, and pitches of the base circuit pattern and the contact part are uniformly and minutely formed.
However, in the case of forming the buried circuit pattern 3 using plating, a difference in plating between an area, in which the pattern groove 2 is formed, and the rest of the area is generated. Thus, upon etching after plating, the etching is not uniformly performed. Accordingly, like FIG. 1, since the etching is not performed at one area of the circuit pattern 3, a short between the adjacent circuit patterns occurs, and since the etching is excessively performed at another area, an error in signal transmission occurs.